Post Tagged with: "Arthritis"

Long-term Experiments

I recently read this Nature article, where is described what is probably one of the longest experiments ever to be conducted. A population of E. coli was kept for 20 years (!) in a nutrient solution (low on glucose), and samples were taken and deep-frozen after 2000, 5000, 10000, 15000, 20000 and 40000 generations. The authors sequenced the genome of the sample bacteria to investigate the rate of mutations.

Up to generation 20K, the number of mutations grew steadily to a total of 45. The adaptation to the environment, however, only increased strongly in the beginning. It was concluded that the most beneficial mutations were the first to occur. After generation 20K, a change in the mutT gene caused a rapid increase in the mutation rate to result in 653 mutation at generation 40K, but with a neutral signature, i.e. no further adaptation.

What I find most fascinating about this extreme long-term experiment is the confidence of the researchers that it would be possible to analyze the genes at a later point; this was not at all self-evident in the late ’80s! In addition, some work had to be done each day, for twenty years. What if the power had failed for a week or so? Of course, this unique opportunity to watch evolution as it happens is very intriguing.

An experiment that took even longer was awarded this year’s Ig Nobel Prize in medicine: Donald L. Unger of Thousand Oaks, CA, cracked the knuckles of his left hand, but not his right hand, every day for 50 years to see if knuckle-cracking leads to arthritis. After this time, both hands were fine, so he concluded: “While a larger group would be necessary to confirm this result, this preliminary investigation suggests a lack of correlation between knuckle cracking and the development of arthritis of the fingers.” Apparently, the experiment must be repeated.

By October 23, 2009 2 comments Uncategorized

2009 Ig Nobels!

The 2009 Ig Nobels have been announced.  The chemistry winner is the team of Javier Morales, Miguel Apátiga, and Victor M. Castaño from Mexico for growing diamonds from tequila:

Abstract:  Diamond thin films were growth using Tequila as precursor by Pulsed Liquid Injection Chemical Vapor Deposition (PLI-CVD) onto both silicon (100) and stainless steel 304 at 850 °C. The diamond films were characterized by Scanning Electron Microscopy (SEM) and Raman spectroscopy. The spherical crystallites (100 to 400 nm) show the characteristic 1332 cm-1 Raman band of diamond.

Other notables:

  • The Peace Prize goes to Stephan Bolliger, Steffen Ross, Lars Oesterhelweg, Michael Thali and Beat Kneubuehl of the University of Bern, Switzerland for determining whether it’s better to be cracked over the head by a full or empty beer bottle. (doi: 10.1016/j.jflm.2008.07.013)
  • The Medicine Prize goes to Donald L. Unger for investigating whether cracking knuckles leads to arthritis.  He systematically cracked the knuckles of his left hand (but not his right) every day for 60 years.  His findings: neither hand had arthritis showing no correlation between knuckle cracking and arthritis.  Money quote from paper: “This result calls into question whether other parental beliefs, e.g., the importance of eating spinach, are also flawed. Further investigation is likely warranted.”. (doi: 10.1002/1529-0131(199805)41:5<949::AID-ART36>3.0.CO;2-3) (yes, that’s really the DOI)
  • The Public Health Prize goes to Elena N. Bodnar, Raphael C. Lee, and Sandra Marijan for a patent for a brassier which can – in life threatening emergency – be converted into two functional face masks. (US Patent: 7255627) Picture included:


    By October 3, 2009 2 comments science news